From 209a1556083e80141da0e4e2142af104d9de3a27 Mon Sep 17 00:00:00 2001
From: WalterPlinge <22519813+WalterPlinge@users.noreply.github.com>
Date: Wed, 25 May 2022 14:51:37 +0100
Subject: [PATCH] fix a double free bug

---
 src/build_settings.cpp | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/src/build_settings.cpp b/src/build_settings.cpp
index 19de16f93..f9c417ce2 100644
--- a/src/build_settings.cpp
+++ b/src/build_settings.cpp
@@ -1285,11 +1285,14 @@ bool find_msvc_install_from_env_vars(gbAllocator allocator, Find_Result_Utf8 *re
 			}
 
 			// Get the root from the one we found, and make the other
+			// NOTE(WalterPlinge): we need to copy the string so that we don't risk a double free
 			if (result->windows_sdk_um_library_path.len > 0) {
-				result->windows_sdk_root = substring(result->windows_sdk_um_library_path, 0, result->windows_sdk_um_library_path.len - 1 - um_dir.len);
+				String root = substring(result->windows_sdk_um_library_path, 0, result->windows_sdk_um_library_path.len - 1 - um_dir.len);
+				result->windows_sdk_root = copy_string(allocator, root);
 				result->windows_sdk_ucrt_library_path = concatenate3_strings(allocator, result->windows_sdk_root, ucrt_dir, make_string_c("\\"));
 			} else if (result->windows_sdk_ucrt_library_path.len > 0) {
-				result->windows_sdk_root = substring(result->windows_sdk_ucrt_library_path, 0, result->windows_sdk_ucrt_library_path.len - 1 - ucrt_dir.len);
+				String root = substring(result->windows_sdk_ucrt_library_path, 0, result->windows_sdk_ucrt_library_path.len - 1 - ucrt_dir.len);
+				result->windows_sdk_root = copy_string(allocator, root);
 				result->windows_sdk_um_library_path = concatenate3_strings(allocator, result->windows_sdk_root, um_dir, make_string_c("\\"));
 			}